Monday, May 11, 2009

Slow down the stem cell hype

In Science, James Wilson has a piece (abstract here and what appears to be the full piece here) entitled, “A History Lesson for Stem Cells” where he compares the hype around embryonic stem cell research to previously hyped research into gene therapy. Wilson is a proponent of embryonic stem cell research who applauds President Obama’s decision to overturn President Bush’s restrictions on the funding of embryonic stem cell lines yet he warns about the consequences of pushing research too fast.

The field of gene therapy began with laboratory studies in the mid- to late-1980s and grew linearly during the 1990s (see figure, right). Very early in this evolution, clinical trials were initiated, and their number and overall patient recruitment figures grew in step with the science. During that period, gene therapy was touted as a potential cure for a huge array of ailments. By 2000, researchers had launched more than 400 clinical trials, testing the approach against a wide spectrum of illnesses. Yet the Food and Drug Administration concluded in a September 2000 review, "the hyperbole has exceeded the results" and "little has worked" (2). Although the field has improved since then, with notable successes against inherited blindness (3–5) and immune deficiency (6), those successes are shadowed by several tragic adverse events, including treatment-induced cancers in some volunteers (7) and, in 1999, the death of an 18-year-old, Jesse Gelsinger, in a gene therapy clinical trial that I led (8). Gelsinger's death initiated a chain of events that seriously derailed the field.....

Many of the factors that fueled gene therapy's premature expansion are major drivers of the hESC and iPS research agenda today. A large and vocal population of patients suffering from a wide variety of ailments is pressing for stem cell–based therapies. Disease-specific stem cell research groups are more politically sophisticated than ever, in some cases employing congressional lobbyists. Unrealistic expectations have been fueled by relentless media coverage, driven in part by a factor not present in the gene therapy roll-out: a debate over the ethics of research on human embryos and embryo cells, which has served as a "news hook" that brings media attention to even the most incremental of advances.....

Despite advances, our understanding of the biology of hESCs and iPS cells remains thin with regard to clinical safety and utility. Controlled incorporation of transplanted stem cells into host tissues and organs remains a major challenge. Questions about engraftment, rejection, and toxicity abound.

I find it incredibly interesting that this article was written and published only after the restrictions on embryonic stem cell research funding have been removed. It's almost like Science is saying, "Alright guys, we got what we wanted by hyping this research. Now let's tone it down a bit and make sure we know what we're doing before we get someone killed."